2 This file is part of GNUnet
3 Copyright (C) 2014-2017 GNUnet e.V.
5 GNUnet is free software: you can redistribute it and/or modify it
6 under the terms of the GNU Affero General Public License as published
7 by the Free Software Foundation, either version 3 of the License,
8 or (at your option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Affero General Public License for more details.
17 * @brief functions to parse JSON snippets
18 * @author Florian Dold
19 * @author Benedikt Mueller
20 * @author Christian Grothoff
23 #include "gnunet_json_lib.h"
27 * Navigate and parse data in a JSON tree. Tries to parse the @a root
28 * to find all of the values given in the @a spec. If one of the
29 * entries in @a spec cannot be found or parsed, the name of the JSON
30 * field is returned in @a error_json_name, and the offset of the
31 * entry in @a spec is returned in @a error_line.
33 * @param root the JSON node to start the navigation at.
34 * @param spec parse specification array
35 * @param[out] error_json_name which JSON field was problematic
36 * @param[out] which index into @a spec did we encounter an error
37 * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
40 GNUNET_JSON_parse (const json_t *root,
41 struct GNUNET_JSON_Specification *spec,
42 const char **error_json_name,
43 unsigned int *error_line)
50 for (i=0;NULL != spec[i].parser;i++)
52 if (NULL == spec[i].field)
53 pos = (json_t *) root;
55 pos = json_object_get (root,
59 spec[i].parser (spec[i].cls,
63 if (NULL != error_json_name)
64 *error_json_name = spec[i].field;
65 if (NULL != error_line)
67 GNUNET_JSON_parse_free (spec);
71 return GNUNET_OK; /* all OK! */
76 * Frees all elements allocated during a #GNUNET_JSON_parse()
79 * @param spec specification of the parse operation
82 GNUNET_JSON_parse_free (struct GNUNET_JSON_Specification *spec)
84 for (unsigned int i=0;NULL != spec[i].parser;i++)
85 if (NULL != spec[i].cleaner)
86 spec[i].cleaner (spec[i].cls,
92 * Set an option with a JSON value from the command line.
93 * A pointer to this function should be passed as part of the
94 * 'struct GNUNET_GETOPT_CommandLineOption' array to initialize options
97 * @param ctx command line processing context
98 * @param scls additional closure (will point to the 'json_t *')
99 * @param option name of the option
100 * @param value actual value of the option as a string.
101 * @return #GNUNET_OK if parsing the value worked
104 set_json (struct GNUNET_GETOPT_CommandLineProcessorContext *ctx,
109 json_t **json = scls;
112 *json = json_loads (value,
113 JSON_REJECT_DUPLICATES,
118 _("Failed to parse JSON in option `%s': %s (%s)\n"),
122 return GNUNET_SYSERR;
129 * Allow user to specify a JSON input value.
131 * @param shortName short name of the option
132 * @param name long name of the option
133 * @param argumentHelp help text for the option argument
134 * @param description long help text for the option
135 * @param[out] val set to the JSON specified at the command line
137 struct GNUNET_GETOPT_CommandLineOption
138 GNUNET_JSON_getopt (char shortName,
140 const char *argumentHelp,
141 const char *description,
144 struct GNUNET_GETOPT_CommandLineOption clo = {
145 .shortName = shortName,
147 .argumentHelp = argumentHelp,
148 .description = description,
149 .require_argument = 1,
150 .processor = &set_json,
151 .scls = (void *) json